This invention relates generally to a snow ski structure. More specifically, it is concerned with the design of the ski sidecut and the relationship of the skier's foot on the ski to the inside edge and the sidecut of the ski, and how that positioning increases the efficiency of the moment arm about the inside edge, as well as impacting on the turning ability of the ski.
Downhill skiing has increased in popularity since its recreational introduction, focusing attention on the structure and design of skis to produce skis that provide increased speed and greater responsiveness to the improved skiing techniques employed by skiers today. The materials employed in alpine skis have been changed in response to the need to develop higher performance skis at lower manufacturing costs. Materials have been employed which have lightened the weight of the skis, while strengthening them. Today's skis are typically laminated structures with discrete layers of polyethylene, fiberglass, thin layers of rubber and core material, coupled with bottom and top edges, between the bottom running surface and the top facing surface. Little has been done, however, to improve the ability of skiers to control their skis during use or to make it easier to execute turns.
One of the most difficult problems for beginning skiers, and a continuing problem for skiers with intermediate skills, is the ability to control the skis during the initiation and execution of a turn. Properly executed turns are initiated by the gradual shifting of the skier's weight to one ski, which either already is or rapidly becomes the downhill ski, to cause the ski to begin to flex. Specifically, as the skier's weight is moved toward the inside edge of the downhill ski, thus putting the ski up on this edge, the ski begins to flex as the ski skids and slides through its turn.
For the purposes of further discussion, it is to be understood that the term skid or skidding describes movement of the skis across or transverse to the fall line of a ski slope. Similarly, slide or sliding describes movement of the skis parallel to the fall line of a ski slope. A pure carved turn is the desired type of turn and is one in which the ski follows its arc without any transverse skidding. The arc of the ski is the shape of the ski created by its sidecut and flexure.
There are numerous types of skis for the novice to intermediate skier which attempt to provide a product that will accomodate the normally less aggressive skiing style of these non-racing or infrequent skiers. Such skiers will initiate generally wide turns at moderate to high speeds. Most skis have attempted to accomodate skiers in this range by having a short, stiff ski with a center to back-weighted flexural distribution that permits a skidding or sliding technique in turns. Other designs utilize a relatively abrupt flexural transition with low camber and beveling to offer some limited carving capability, in addition to easier skidding and sliding capability. However, none of these types of skis have attempted to make the mechanics of initiating and executing turns easier for the novice and intermediate skier.
The sharpness of the turn executed is based upon the sidecut geometry of the ski; the deeper the sidecut or the longer the arc length or the shorter the radius of curvature forming the sidecut, the sharper the turn that can be executed. However, the amount of effort necessary to initiate a turn and to angulate the ski with respect to the snow surface is partially a function of the positioning of the skier on the skis. In all of the traditional skis, the positioning of the centerline of the foot and the centerline of the ski boot on the ski has generally been over the centerline of the ski extending between the front or shovel and the rear or tail. A skier must exert, therefore, considerable effort to get up or angle the downhill ski on the inside edge and to rotate the skis to initiate a turn and to accomplish a short or tight turn with current designs.
Novice to intermediate skiers, however, do not uniformly, nor properly, execute turning techniques because of inability to put the skis on edge, mistimed and improper rotation of the skis, improper application of pressure to the skis, and improper sequencing of the angulation, rotation and pressure steps.
The foregoing problems are solved in the present invention by providing a ski design which combines deep sidecut geometry and skier placement to assist the skier by providing a mechanical advantage to engage the inside edge. This provides a ski that is responsive turn to turn and initiates carved short radius turns quickly and relatively easily without loss of the rotational skidding and sliding characteristics of a standard ski design.